Abstract：Titanium and titanium alloys are widely used in aerospace, biomedical and other fields because of their
high specific strength, corrosion resistance, and good biocompatibility. Selective electron beam melting (SEBM) is
one of powder bed fusion additive manufacturing technology developed in recent years. It has the characteristics of
high energy density, good production efficiency, low stress, and clean in a vacuum environment. Thus, the titanium
alloys prepared by SEBM technology has become a research hotspot in academia and engineering. This article summarizes
the research progress of Ti-6Al-4V alloy prepared by SEBM technology, focusing on the analysis of
defects, microstructure and mechanical property, and finally prospects the development and application of SEBM
technology. The research progress of SEBM fabricated titanium alloy is summarized to provide reference for its
application in related fields. This article focuses on the analysis of defects, microstructure and mechanical property
of Ti- 6Al- 4V alloy prepared by SEBM technology, and finally prospects the development and application of
SEBM technology. In the SEBM manufactured Ti-6Al-4V alloy, there are two kinds of defects, irregularly shaped
pores (with unfused particles) and spherical holes. The columnar crystals, acicular α' martensite structure and massive
phase are obtained in the titanium alloy, and some methods are used to transform these microstructures into α+
β lamellae, eliminate columnar crystals. The mechanical properties of Ti- 6Al- 4V alloy fabricated by SEBM are
anisotropic, and strength of the as-built alloy in the vertical direction are higher than those in the horizontal direction,
and the elongation in the vertical direction is higher than that in the horizontal direction. There are a large
number of columnar primary β grains in Ti-6Al-4V titanium alloy prepared by SEBM, which are parallel to the construction direction. The microstructure of the alloy consists of acicular α' martensite, massive αm and layered α-β.
Thin layer of α and β phase follows the Burgers orientation relationship, namely the [111]//[ 21ˉ1ˉ0 ]，(110)//(0002)，
and [111]//[12ˉ13ˉ]，( 01ˉ1ˉ)//( 01ˉ11). The β phase and α phase of Ti-6Al-4V alloy have strong texture, and the β phase
has strong {100}<001> texture. Mechanical properties of alloys are anisotropic and fine lamellar α- β structure
improves mechanical properties of alloys.
2022, Vol. 32 
